US3383088A - Plug valves - Google Patents

Plug valves Download PDF

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Publication number
US3383088A
US3383088A US524697A US52469766A US3383088A US 3383088 A US3383088 A US 3383088A US 524697 A US524697 A US 524697A US 52469766 A US52469766 A US 52469766A US 3383088 A US3383088 A US 3383088A
Authority
US
United States
Prior art keywords
sleeve
plug
pressure
valve
port
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US524697A
Other languages
English (en)
Inventor
Donn W Duffey
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Flowserve Corp
Original Assignee
Duriron Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Duriron Co Inc filed Critical Duriron Co Inc
Priority to US524697A priority Critical patent/US3383088A/en
Priority to FR84300A priority patent/FR1500729A/fr
Priority to BE690140D priority patent/BE690140A/xx
Priority to GB53224/66D priority patent/GB1160290A/en
Priority to NL6617979A priority patent/NL6617979A/xx
Priority to DE19671600737 priority patent/DE1600737B1/de
Priority to AT46667A priority patent/AT278456B/de
Priority to CH72367A priority patent/CH461207A/de
Priority to ES0336287A priority patent/ES336287A1/es
Priority to SE1547/67A priority patent/SE322383B/xx
Application granted granted Critical
Publication of US3383088A publication Critical patent/US3383088A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K5/00—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary
    • F16K5/02—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary with plugs having conical surfaces; Packings therefor
    • F16K5/0257—Packings
    • F16K5/0271—Packings between housing and plug
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K27/00—Construction of housing; Use of materials therefor
    • F16K27/06—Construction of housing; Use of materials therefor of taps or cocks
    • F16K27/062—Construction of housing; Use of materials therefor of taps or cocks with conical plugs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K39/00—Devices for relieving the pressure on the sealing faces
    • F16K39/06—Devices for relieving the pressure on the sealing faces for taps or cocks
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K5/00—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary
    • F16K5/02—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary with plugs having conical surfaces; Packings therefor
    • F16K5/0207—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary with plugs having conical surfaces; Packings therefor with special plug arrangement, e.g. special shape or built in means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K5/00—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary
    • F16K5/02—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary with plugs having conical surfaces; Packings therefor
    • F16K5/0257—Packings
    • F16K5/0264—Packings in the housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K5/00—Plug valves; Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary
    • F16K5/08—Details
    • F16K5/14—Special arrangements for separating the sealing faces or for pressing them together

Definitions

  • the present invention relates to an improved plug valve, and more particularly to a plug valve including a fluorocarbon sleeve having a pressure relief area capable of bursting in the event of a build-up of the pressure above a predetermined minimum to relieve the pressure between the sleeve and the body.
  • Plug valves of the type to which the present invention relates include a body provided with a bore, and a plug which is received in a fluorocarbon sleeve also positioned in the bore.
  • the sleeve provides a seal and a surface which possesses a relatively low coeflicient of friction.
  • the valves of this general type are used with corrosive liquids, and thus the sleeve is preferably made of polytetrafluoroethylene.
  • Typical valve structures include those described in US. Patents 2,713,987, 2,728,550, 2,729,420, 2,735,645, 2,961,214, 2,913,219, 2,987,295, 3,146,286 and 3,199,835, all assigned to the assignee of this application.
  • Polytetrafluoroethylene is a resin which is more easily deformable at elevated temperatures, and also shows a tendency to permit permeation therethrough of low molecular weight gases and the like.
  • valve service there is a tendency for the valve sleeve to bulge inwardly into the openings of the port when the plug is in the closed position. This condition is due either to passage of fluid between the sleeve and the body on the upstream side, because the line pressure causes the plug to be forced tightly in a downstream direction against the sleeve, or because of permeation of low molecular weight materials through, the sleeve itself, or a combination of both.
  • the effect is to provide a build-up of pressure between the sleeve and the body particularly if there is a rapid heating of the valve up to about 350 F. by an outside source which causes inward deflection of the sleeve into the plug ports.
  • an outside source which causes inward deflection of the sleeve into the plug ports.
  • vent holes in the sleeve located 90 with respect to the body ports thereby providing free and unobstructed flow of fluid between the back side of the sleeve and the plug port with the plug in the closed position.
  • Such an arrangement is shown, for example, in US. Patent 3,066,- 909. While the use of vent holes operates satisfactorily to prevent a pressure build-up on the back side of the sleeve, they also permit passage of fluid from the plug port to the back side of the sleeve when the plug is in the closed position.
  • the disadvantage of this arrangement is that some types of .valve service require that the material flowing through the valve remain free of contaminants.
  • the Valve may be handling one type of fluid at one time, which may act as a contaminant for other fluids which thereafter flow through the valve.
  • some materials for example, reactive monomers which solidify on standing, unobstructed flow to the back side of the sleeve allows these materials to collect and solidify, resulting in sleeve failure on operation of the valve.
  • this particular problem appears to be limited in occurrence to services which include low molecular weight monomeric materials and/ or low molecular weight gases.
  • the sleeve is protected by a pressure relief area which is so positioned in the sleeve as to be in alignment with the plug ports with the plug in the closed position.
  • the pressure relief area is preferably a portion of the sleeve having a thickness dimension less than the thickness of the sleeve surrounding the relief area.
  • the sleeve provides a continuous seal element free of any passageways which permit flow of fluid from the plug port to the back side of the sleeve.
  • the pressure relief area operates only as a safety feature to protect the sleeve in those instances wherein pressure conditions exist tending to cause turning or tearing of the sleeve as previously noted. Additionally, even if the pressure relief area bursts because of the existence of pressure pockets, the flow from the plug port to the back side of the sleeve is at a substantially smaller rate than if there were a vent hole in the sleeve permitting unobstructed flow therethrough in either direction.
  • Another object of the present invention is to provide a plug valve utilizing a fluorocarbon sleeve wherein the sleeve is provided with pressure relief areas which are aligned with the plug port in the closed position of the plug, and which are capable of bursting above a predetermined pressure to permit equalization of the pressure from the back side of the sleeve into the plug port while permitting only obstructed flow in the reverse direction.
  • a further object of the present invention is the provision of a plug valve utilizing a polytetrafluoroethylene seal element which includes spaced pressure relief areas arranged to the body ports and alignable with the plug port in the closed position of the valve, wherein the relief areas are designed to burst above a predetermined minimum pressure to protect the sleeve, the relief areas on bursting providing flow from the back side of the sleeve into the plug port which is at a substantially greater rate than that from the plug port to the back side of the sleeve.
  • FIG. 1 is a view partly in section and partly in elevation of a plug valve in accordance with .the present invention
  • FIG. 2 is a sectional view along the lines 22 of FIG. 1 with the plug in the closed position;
  • FIG. 3 is an enlarged fragmentary section of FIG. 2;
  • FIG. 4 is an enlarged fragmentary section showing the details of the pressure relief area in the sleeve in accordance with the present invention.
  • the valve in FIGS. 1 and 2 includes a body 29 having a conical bore 21 extending transversely therethrough from the top of the body and having its bottom end closed by an integral portion 22 of the body. Ports 23 and 24 open into the bore 21 from opposite sides of the valve body, and flanges 25 are provided at the outer ends of the port for attachment to pipes in the usual way.
  • annular shoulder is provided at the lower end of the tapered portion of the bore 21, the inner diameter of the shoulder being appreciably less than the minimum diameter of the tapered portion of the bore.
  • this shoulder 30 the surface of the bore is provided with a preferably continuous annular groove 31 of substantially greater diameter than the portion of the bore immediately thereabove, and thus the bore includes a continuous annular land 32 extending around the lower end of the tapered surface of the bore.
  • a counterbore 34 terminating in an annular shoulder 35 and spaced below this shoulder is a second circumferential groove 36 similar to groove 31.
  • a circumferential land 37 is positioned below this groove 36 on the bore surface similar to the land 32 adjacent the lower end of the bore and similarly extending continuously around that surface of the "bore.
  • the surface area of the bore between the land portions 32 and 37 is provided with a plurality of pockets 41 and 42 which may be of the same depth as the grooves 31 and 36 as compared with the adjacent surface portions of the bore.
  • a tapered valve plug is received within the bore 21 and is of sufliciently smaller radial dimensions than the bore to establish an annular clearance therebe tween.
  • Received in the annular clearance is a sleeve of fluorocarbon resin, preferably polytetrafluoroethylene, for providing the desired sealing action between the plug and the body.
  • the plug is provided with a through port 56 adapted for alignment with the body ports 23 and 24 and liner ports 57 and 53.
  • the upper end of the valve body 20 is closed by a cap 60 secured to the body by screws 61 and the inner portion of the cap clamps an annular polytetrafluoroethylene diaphragm 62 on the shoulder 35 to provide a seal.
  • the plug includes a stem 65 which projects through the cap 60 and is provided with flats 66 on each side thereof for engagement with an operating handle in the usual way. Sealing pressure of the plug with the sleeve 55 is maintained by means of a thrust collar 67 which is in contact with a washer 68 which in turn engages the upper surface of the plug through the diaphragm 62, the thrust collar 67 being forced against the plug by an adjustor 69 secured to the cap 60 by screws (not shown).
  • the diaphragm also acts as a plug stem seal.
  • the inlet port 23 of the body, and the inlet side of the plug 56a are preferably so constructed and arranged that during rotational movement of the plug from the open position to the closed position, the outlet port 24 closes entirely while the interior of the plug port continues in direct fluid receiving relationship with the inlet port of the body and substantially the same pressure as inlet pressure.
  • the portion of the sleeve generally designated 70 is prevented from being deflected inwardly and torn as the plug is turned.
  • a pressure relief area 75 positioned on the outer surface of the sleeve and facing the body, as shown in FIG. 3.
  • the pressure relief area will burst releasing the pressure behind the sleeve into the plug port thereby preventing turning or tearing of the sleeve.
  • the sleeve Until after bursting at the pressure relief area, the sleeve is free of holes or apertures other than the ports 57 and 58 and thus, a continuous seal area is provided which substantially eliminates the accumulation of fluid materials between the valve body and the opposed surface of the sleeve.
  • the pressure relief area acts as a safety feature in those exceptional instances in which temperature, pressure or types of service, or combinations thereof give rise to accumulation of pressure behind portions 71 and 72 of the sleeve. It is to be understood that in normal use of the valve, the continuous nature of the seal provided by the sleeve substantialy eliminates the accumulation of fluids between the sleeve and the body.
  • the pressure relief area is preferably a circular cavity having a diameter a of between A to /43 of an inch.
  • the relief area may be conveniently placed in the sleeve by drilling with a drill having an included angle b at the point thereof between 110 and 130.
  • the depth of drilling is suflicient to provide a relatively thin membrane-like section having a dimension at c of between 0.010 and 0.022 of an inch.
  • the diameter of the relief area be between A to of an inch with an included angle of between 105 to 120 to provide a membrane-like section 80 which is between 0.010 and 0.015 of an inch thick, thus rupturing at a pressure less than that which will cause damage to the sleeve either by tearing or turning.
  • the membrane 80 does not permit unobstructed flow in both directions, that is, the rate of flow into the plug port is substantially greater than the rate of flow from the plug port to the back side of the sleeve.
  • the rate of flow into the plug port is substantially greater than the rate of flow from the plug port to the back side of the sleeve.
  • the flow through the ruptured membrane to the plug port was approximately 1950 cubic centimeters per minute while flow from the port through the same ruptured membrane to the back side of the sleeve was approximately 214 cubic centimeters per minute.
  • the flow rate into the plug port was 120 cubic centimeters per minute while flow from the plug port to the back side of the sleeve was very slight and immeasurable.
  • the relief area operates as a check valve, relieving pressure on the back side of the sleeve but tending to prevent reverse flow of fluid from the plug port to the back side of the sleeve.
  • the pressure in the plug port far exceeds the pressure on the back side of the sleeve, there will be some flow, but at a far lower rate than if the back side of the liner were at the same greater pressure as the plug port.
  • This feature is of significance since it tends to prevent unobstructed flow of fluid from the plug port to the back side of the sleeve while at the same time permitting flow in the reverse direction to relieve pressure, if needed, in order to protect the sleeve.
  • a plug valve including a body having a bore, ports opening into said bore, a fluorocarbon resin sleeve received in said bore, said sleeve having openings therein communicating with said ports, a valve plug received in sealing relation is said sleeve, a port in said plug communicating with said body ports in the open position of the valve and sealed by said sleeve in the closed position of said valve, said sleeve being deformable into said plug port in the closed position of the valve by accumulation of pressure between the body and the opposed facing portion of the sleeve, said sleeve including means defining a pressure relief area which bursts at a pressure above a predetermined minimum to relieve said accumulated pressure into the plug port, portions of said sleeve other than the relief area being capable of withstanding pressure above said predetermined minimum, and said pressure relief area being so located in said sleeve that in the event of pressure conditions above said predetermined minimum the pressure between the body and the portion of the sleeve facing the plug
  • valve body includes pocket means positioned in said bore between said body ports, said sleeve including portions thereof received in said pocket means, and said pressure relief area being located in the portion of the sleeve received in said pocket means.
  • a plug valve as set forth in claim 2 including means in said body bore to prevent axial and rotary movement of said sleeve relative to said bore.
  • a plug valve as set forth in claim 1 wherein said pressure relief area of said sleeve comprises a portion of said sleeve having a thickness dimension less than the thickness of the sleeve surrounding said relief area, and said area of lesser thickness operating in response to pressure above said minimum causing bursting across only a small segment of said pressure relief area.
  • a plug valve as set forth in claim 1 wherein bursting of said pressure relief area in response to pressure above said minimum provides for flow of fluid from behind said sleeve to said plug port at a rate greater than the rate of flow from said plug port to the area between said sleeve and body.
  • a valve plug as set forth in claim 1 including pockets in said body which receive portions of said sleeve, and wherein there is a pressure relief area in the portion of the sleeve received in each of said pockets, and said pressure relief areas upon bursting permitting a flow from said pocket to said plug port which is greater than the flow from said plug port to said pocket.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Taps Or Cocks (AREA)
  • Safety Valves (AREA)
  • Portable Nailing Machines And Staplers (AREA)
  • Reciprocating Pumps (AREA)
US524697A 1966-02-03 1966-02-03 Plug valves Expired - Lifetime US3383088A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
US524697A US3383088A (en) 1966-02-03 1966-02-03 Plug valves
FR84300A FR1500729A (fr) 1966-02-03 1966-11-21 Vanne de sécurité
BE690140D BE690140A (de) 1966-02-03 1966-11-24
GB53224/66D GB1160290A (en) 1966-02-03 1966-11-28 Rotatable Plug Valves
NL6617979A NL6617979A (de) 1966-02-03 1966-12-21
DE19671600737 DE1600737B1 (de) 1966-02-03 1967-01-13 Druckausgleichseinrichtung in einer in einem Absperrhahn zwischen Gehaeusebohrung und Kueken eingelegten Dichtungsbuchse aus Fluorkohlenstoffharz
AT46667A AT278456B (de) 1966-02-03 1967-01-17 Absperrhahn
CH72367A CH461207A (de) 1966-02-03 1967-01-18 Absperrhahn mit Küken
ES0336287A ES336287A1 (es) 1966-02-03 1967-01-31 Perfeccionamientos en la construccion de valvulas de macho.
SE1547/67A SE322383B (de) 1966-02-03 1967-02-03

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US524697A US3383088A (en) 1966-02-03 1966-02-03 Plug valves

Publications (1)

Publication Number Publication Date
US3383088A true US3383088A (en) 1968-05-14

Family

ID=24090302

Family Applications (1)

Application Number Title Priority Date Filing Date
US524697A Expired - Lifetime US3383088A (en) 1966-02-03 1966-02-03 Plug valves

Country Status (10)

Country Link
US (1) US3383088A (de)
AT (1) AT278456B (de)
BE (1) BE690140A (de)
CH (1) CH461207A (de)
DE (1) DE1600737B1 (de)
ES (1) ES336287A1 (de)
FR (1) FR1500729A (de)
GB (1) GB1160290A (de)
NL (1) NL6617979A (de)
SE (1) SE322383B (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3589679A (en) * 1969-11-28 1971-06-29 Duriron Co Plug valve
WO2009129770A1 (de) * 2008-04-21 2009-10-29 Voelker Manfred Probe-entnahmeventil
WO2010081864A1 (en) 2009-01-15 2010-07-22 Nihab Ab A valve and a method for providing such a valve
US11592115B2 (en) * 2018-11-22 2023-02-28 Rosemount Aerospace Inc. Fluid valve
US11788631B2 (en) * 2020-02-28 2023-10-17 Columbia Insurance Company Barrel valve

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2143930B (en) * 1983-07-21 1986-07-30 Mapegaz Remati Sa Plug valves
DE4405089A1 (de) * 1994-02-17 1995-08-31 Walter Egon Kraus Absperrvorrichtung für Fluids, insbesondere für eine Flüssigkeit
GB2424465B (en) * 2005-03-24 2008-09-17 Parker Hannifin Plc Rising plug valve seat

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2994504A (en) * 1958-09-04 1961-08-01 Continental Mfg Company Plug valve
US3066909A (en) * 1959-10-26 1962-12-04 Continental Mfg Company Plug valve

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE60457C (de) * F. GRAEF in Aichach Gummiplättchen mit Stichloch als Sicherheitsventil für hochgespannte Gase
US2987295A (en) * 1959-07-24 1961-06-06 Duriron Co Plug valves
US3116747A (en) * 1961-06-05 1964-01-07 Torrington Co Unitary rupturable check valve

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2994504A (en) * 1958-09-04 1961-08-01 Continental Mfg Company Plug valve
US3066909A (en) * 1959-10-26 1962-12-04 Continental Mfg Company Plug valve

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3589679A (en) * 1969-11-28 1971-06-29 Duriron Co Plug valve
WO2009129770A1 (de) * 2008-04-21 2009-10-29 Voelker Manfred Probe-entnahmeventil
WO2010081864A1 (en) 2009-01-15 2010-07-22 Nihab Ab A valve and a method for providing such a valve
US8740186B2 (en) 2009-01-15 2014-06-03 Nihab Nordisk Industrihydraulik AB Valve and a method for providing such a valve
US11592115B2 (en) * 2018-11-22 2023-02-28 Rosemount Aerospace Inc. Fluid valve
US11788631B2 (en) * 2020-02-28 2023-10-17 Columbia Insurance Company Barrel valve
US20230417330A1 (en) * 2020-02-28 2023-12-28 Columbia Insurance Company Barrel valve

Also Published As

Publication number Publication date
FR1500729A (fr) 1967-11-03
AT278456B (de) 1970-02-10
SE322383B (de) 1970-04-06
NL6617979A (de) 1967-08-04
BE690140A (de) 1967-05-02
ES336287A1 (es) 1967-12-16
CH461207A (de) 1968-08-15
GB1160290A (en) 1969-08-06
DE1600737B1 (de) 1970-09-24

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